Spraying machine



p 1956 M. H. TUFT I 2,762,651

SPRAYING MACHINE Filed D80. 28, 1 955 3- Sheets-Sheet l IN VEN TOR, 11/556 16. 7Uf7' Sept. 11, 1956 M. H. TUFT SPRAYING MACHINE Filed Dec. 28, 1953 INVENTOR,

M/ZES H. 70F) 2,762,651 SPRAYING MACHINE Miles H. Tuft, Huntington Park, Califi, assignor to Hardie Manufacturing Company, Hudson, lVIich., a corporation of Michigan Application December 28, 1953, Serial No. 400,481

4 Claims. (Cl. 2"99-29) This invention relates to machines for spraying trees and crops with insecticides and similar materials, and more particularly relates to that type of spraying machine in which the liquid carrying the insecticide is carried and cominuted into a fine spray by'a blast of carrier It is an object of this invention to provide a machine having an air blast of great force and volume, whereby spray may be carried to great heights and distances from a machine of the ordinary truck or trailer type without use of booms or towers.

A further object of this invention is to provide a very compact spraying machine of the opposed dual-fan type, machines of this type having hitherto been so elongated as to be maneuverable only with difficulty in fruit orchards.

Another object of this invention is to provide a dualfan type of spraying machine which delivers an air-blast concentrated into a radial zone of very little thickness, so that the need of dual liquid injector systems is obviated and the velocity of the blast is enhanced.

Still another object of my invention is to provide a spraying machine in which the air-blast, although developed by dual fans and of consequent large volume, is so delivered in what amounts to a single plane that very simple directional controls may be applied to the blast.

In general terms, I accomplish the foregoing objects and other advantages and improvements which will become apparent as the following specification proceeds, by disposing two fans in opposite ends of a very short cylindrical housing, the length of the housing cylinder being only great enough to provide a single row of peripheral orifices in the upper side wall of the cylinder for egress of air drawn by the fans into the cylinder. The airblasts from the two opposed fans meet within the casing but in a manner hereinafter described in detail not repellant to either of them and emerge through the peripheral orifices as a unified blast of great force and volume. Hitherto it has been attempted to utilize two fans on spraying machines in order to obtain the double volume of air which would seemingly result by the logic of simple arithmetic. However it has always been found that one blast repelled the other, that efiicient air-flow was destroyed by resultant turbulence, and that the net result was often less than the efiect of a single fan, unless the two blasts were guided separately to their point of emergence, which necessitated a machine of enlarged and complex structure. In my invention, instead of a zone of conflict and opposition or an alternative structure of complex wind-tunnels, what may be termed a neutral zone is created at the center of the housing from which airblasts aligned with the axes of the fans are excluded; air entering the housing adjacent to the peripheral exit orifices is allowed and assisted to take the shortest paths to the orifices; and air entering the housing at points moredistant from the exit orifices and particularly at points across the central neutral zone from the orifices is guided into the neutral zone in a direction toward the orifices, whereby it sets up a unified directional flow, instead of turbulence, at the center of the housing and adds its volume, force and directional influence to those of the shortpath air currents previously mentioned.

In the accompanying drawings, illustrative of a presently preferred embodiment of my invention,

States Patent 2,762,651 Patented Sept. 11, 1956 Fig. 1 is a side elevational view of a spraying machine embodying my invention, showing how the blower of the machine may be closely coupled to a storage tank and pumping engine in a vehicle of moderate length.

Fig. 2 is an enlarged transverse vertical sectional view on the line 2-2 of Fig. 1, showing the system of movable bafiles which provide directional control in the peripheral outlets;

Fig. 3 is a longitudinal vertical sectional view on the line 33 of Fig. 2, and on the same scale, illustrating the positions of opposed fans in relation to the central cowled zone and the outlets, and the means for directing air-flow across the central zone toward the outlets; and

Fig. 4 is a transverse horizontal sectional view on the line 44 of Fig. 2, showing in plan a preferred arrangement of said air-flow directing means.

Having reference now to the details of the drawings, there is shown in Fig. 1 a vehicle of trailer type mounted on wheels 6 and having a storage tank 7 for liquid insecticides carried centrally above the wheels. Forwardly of the wheels is a pumping engine, indicated by its ventilated cowling 8 and a platform 9 on which an operator may stand. A draw-bar, not shown, may extend from the platform 9, for connection to a tractor. The blower 10, in which the concepts of the present invention are embodied, is mounted at the rear of the vehicle. A shaft 11 extends rearwardly from the engine through the tank 7 and axially through the blower 10 where it supports for rotation the dual fans of the blower. The shaft 11 is also preferably connected by a chain 12 to a pump 13 which through conduits 14 supplies liquid to a nozzle ring 15. It will be understood that the shaft 11 is also available for driving stirring devices, not shown, within the tank 7. Control devices 16 may be made available close to the operators station, with suitable leads 17 to the engine and to valves, not shown, on intake lines to the pump 13.

The blower 10 has a casing 20 in which two oppositely opening funnel-shaped members 21 and 22 are joined to end walls 23 and 24 which are spaced apart at their central portions to define a chamber 25 of generally cylindrical shape which may be quite short in length in comparison to its diameter. For considerably more than half their peripheries the end walls 23 and 24 converge beyond the chamber 25, leaving between them a circumferential opening 26. In this portion of their peripheries the end walls 23 and 24 are held spaced by bolts 27 and have mounted between them a plurality of valve plates 28, hinged on bolts 29, as described in my copending application Serial No. 242,510, filed August 18, 1951, now Patent No. 2,670,566, in connection with a dust blower. By loosening and then tightening the bolts 27, the valve plates 28 may be secured by the pressure of the slightly flexible end walls 23 and 24 in adjusted positions in which they divide the circumferential opening 26 into a plurality of outlet orifices 30 and control the direction of the air blasts issuing therefrom. In the remaining portion of their peripheries, which in a blower of this type will preferably be the bottom portion, the end walls 23 and 24 are joined by a side wall 31.

The shaft 11 extends through the center of the chamber 25 and has secured to it two fan-type impellers 32 and 33 mounted at opposite ends of the chamber 25 and in opposed operational relationship so as to blow opposed blasts toward the central diametrical plane of the chamber 25. The impellers 32 and 33 preferably have central disks 34 to which blades 35 are diagonally secured, only the blade portions extending radially beyond the disks 34 being effective to propel air into the chamber 25. Secured respectively to the funnel members 21 and 22 by suitable braces 36 are cowlings 37 and 38, each provided with bearings 39--supporting' the shaft 4 11. and 38 are substantially coextensive with the disks 34. Thebraces 36 may be strapsor rods of small magnitude answerin little resistance to air-flo'w," so that thesp'aees between the cowlings 37 and'38 'andthe funnels 21and' 22'aresubstantially unimpeded annular inlet orifices 40 and "41," juxtaposed annularly tothe blades 35 f the respective impellers .32 and .33, and admitting, to the chamber 25 through said blades; Obviously the disks 34 also serve to define the annular orifices and 41 and to screen the central portion of the chamber 25*from direct entry of air; the cowlings 37 and 38, by their outwardly convex shape, have the added functionof assisting the funnels 21 and 22 in streamlining the flowof" a large volume of air into the inlet orifice.

Extending inwardly of the chamber 25 from the side winter in the central diametric plane of the chamber is a bafile plate 44. The plate 44' extends to about the level of the edges of the disks 34, so as to form a barrier between segments of the annular inlet orifices 40 and 41 -adjacent-the wall 31. Aplurality of plates '45' are secured to theplate 44 at right angles thereto and extend inwardly of the chamber 25 substantially coextensively with the plate 44'. The plates are preferably slightly inclined from the wall 31 in the direction of rotation of the impellers 32 and 33. Their number and spacing will depend upon the proportions of the segments of the orifices 40 and,41' between which the plate 44 imposes a barrier to the remainder of those orifices. The function offthe plate 44 is to prevent opposed air blasts entering that portion of the chamber 25 from meeting and causing fluctuating turbulence, and the combined function of the plate 44'and plates is to deflect the so-baffled air blasts to and across the relatively dead space between the disks 34towards the outlet orifices 30. The length of the baflled segments -of the inlet orifices 40 and41 will depend upon the proportion of the periphery'of the casing 20 which it desired to'have'available for the outlets 30, but the battle system comprising the plates 44 and 45 need not and preferably should not extend .inwardly'into the dead ,space between the disks '34 but .should't'errn'inate short of the central zone of the chamber 25.

Mounted on'thenozzle ring 15 are a plurality of nozzles preferably one juxtaposed to each of the outlet orifices 30. The nozzles 50 are inclined to the'central 'diarnetric plane of the blower so that jetsof liquid issuing The cowlings 37 from them are caught and carried by the jets'of air issuing from the orifices. 30. The ring 15 may be "a' split ring,

of which one half serves theorifices 3t on'one 'side of the blower and one half serves the orifices 30 on the other side of the'blower. In that case,'the'two'half rings may be served by individual pumps 13. Thenozzles 50 are preferably individually valved, and the valve'plates 28 of the orifices 30 corresponding to nozzlesISO temporarily not-in use may be turned to close theirrespective orifices 30, thus adding to the force of the air'issuing from the orifice which are left open.

In the operation of the blower, air will 'be drawn into the chamber 25 by the impellers 32 and 33 in opposed annular blasts, a relatively dead air space being formed between the disks 34. Even though'the air will naturally turn to seek the outlets 30, if the air blasts were permitted to meet head-on throughout their annular extent, there would be great turbulence within the chamber 25, and the force at the various outlets .30 wouldfluctuate. By giving direction to a relatively small portion of the total air by means of the plates 44 and 45, a directional pat- ]tern forall of the air is established in which'turbulence at the center of the'chamber 25 is changed to a relatively steady flow towards the outlets. This flow assists'the flow of the major portion of the air in taking short direct paths to the outlets, and the force at the outlets is made relatively constant.

I claim;

1. In a machine for spraying liquids by means of car- 4 rier air blasts-:-a--casing having two opposed end walls spaced to define a single chamber between them, said walls being inclined toward one another throughout a portion of their outer margins to provide a restricted passage from said'charnber, saidcasing having outlet orifices within said restricted passage, and having a closure wall connectingi'saidend Walls so 'as to close'egress from said chamber except throughsa id outlet orifices, each of said end walls having annular opposed inlet orifices; a pair of impellers rotatably mounted within said chamber and arranged to impel air from said inlet orifices toward the-central plane of said chamber in opposed blasts; a baflle within said chamber extending inwardly from said clo'surewa'll generally parallel to and equidistant from said end walls," said baffle intervening between segments of said inlet orifices adjacent said closure Wall and arranged to deflect that portion ofthe air blasts entering said chamber through inlet orifices adjacent said closure wall-across said chamber substantially at right angles to and into 'theremai'ning portion of the air blasts and toward said outlet orifices, whereby all of the air entering said chamber is pneumatically guided towards said outlet orifices and is compressed between said convergent portions of said end 'walls'; and a nozzle ring outside of saidcasing-having a plurality of "nozzles arranged to inject'liquid into air jets issuing from said outlet orifices in jets convergent with the air jets.

2. In "a machineforspraying liquids by carrier air blasts',*a casing'having two opposed end walls and a side wall enclosing a chamber, said "side wall having outlet orifices in'a portion ofits periphery, and having a closed portion; means'for "introducing liquid into air issuing from said orifices; imp ellers respective to each of said end walls and-rotatable in parallel planes soa's to blow opposed air blasts't'oward the central plane of said chamher, said end 'walls having air inlets admitting to said impellers, "and' a baffle 'system extending inwardly between said impellers from the closed portion of said side wall so as'to'intervene between "air blasts generated in opposed'segments of the fields of rotation of said impellets adjacent'to said closed "portion and to deflect the so baified air towards the-central portion of said chambersaid'baflie-sys'tem comprising a first plate disposed in'a plane parallel to said impellers and at least one plate disposed in a plane at 'rightangles to said first plate and extendingon'both sides of said'first plate, said plates terminating s'ho'rt of said central portion.

3. In a machine forspraying liquids, the construction set'for'th'in claim-2, and means shielding the central portions of saidimpellers so as to prevent the direct entry of air into the center "of said casing between said impellers, said airinlets'bei'rig' radially beyond said shielding means 4. In a blower: a casing defining a short generally cylindrical single chamber'and having parallel end walls, said end walls having annularly arranged inlet orifices admitting to sa'id'sing l'e chamber; two fans mounted rotatably within said casing in spaced opposed operative relationship and havingtheir blade ends in 'annular'juxtaposition to said inlet orifices; said casinghaving a circumferential wall having radial air outlets between said fans in a major circumferential portion of said wall and having-aclosed-minor circumferential portion; and baflles disposedbetwee'n' said'fans on that one side of the' axis of rotation of said fan's-adjacent said closed wall portion so as to deflect'oppos'edair blasts across'the space within said casing centrally disposed' with respect to said inlet orifices toward-said outlet'orifices, said baflies then terminating so as to permit said deflected air blasts to become a unified-stream within said casing.

References Citedin the file of this patent UNITED STATES PATENTS 2,608,441 Daugherty Aug. 26, 1952 

